<section class="channel-group">
    <div class="channel-group__header">
        <h2 class="channel-group__title">限时免费</h2>
    </div>
    <ul class="book-table">
        <li v-for="item in free" v-if="$index < 6">
            <div class="u-book">
                <div class="book-cover">
                    <img :alt=item.ad_name
                         src="http://cover.read.duokan.com/mfsv2/download/fdsc3/p01K2lOxEjqn/2mpNESaGLfSSAU.jpg!s">
                    <div class="u-tagRT -freefiction"></div>
                </div>
                <div class="book-info">
                    <h3 class="title">{{item.ad_name}}</h3>
                </div>
            </div>
        </li>
    </ul>
    <a class="channel-grounp__footer" href="/free">更多限免佳作&gt&gt</a>
</section>